## Facts

- The 1868 Fort Laramie Treaty created the Great Sioux Reservation, including the Black Hills, for the tribe’s “absolute and undisturbed use and occupation,” and required approval by three-fourths of adult male Sioux for any cession.
- After an 1874 military expedition reported gold in the Black Hills, non-Indian settlement pressure increased.
- In 1876, federal commissioners obtained an “agreement” to relinquish the Black Hills from only about 10% of adult male Sioux, in exchange for subsistence rations.
- Congress enacted the 1877 Act, implementing the agreement and ending Sioux rights in the Black Hills despite the treaty’s assent requirement.
- The Sioux protested for decades; Congress in 1920 authorized suit in the Court of Claims.
- In 1942, the Court of Claims dismissed, treating the claim as nonjusticiable and not subject to review for adequacy of compensation.
- Under the 1946 Indian Claims Commission Act, the Sioux pursued the claim again; the Commission and Court of Claims found a taking and rejected a res judicata bar.
- In 1978, Congress enacted a statute authorizing merits review of the Black Hills claim as though not previously decided; the Court of Claims awarded principal plus interest from 1877.
- The Supreme Court reviewed the case after the United States sought certiorari.

## Issues

1. Whether Congress violated separation of powers by authorizing merits reconsideration of the Sioux claim despite a prior final judgment.
2. Whether the 1877 Act’s dispossession of the Black Hills constituted a taking of treaty-protected property requiring just compensation, including interest, under the Fifth Amendment.

## Decision

- The Court affirmed, holding (8–1) that the 1978 statute permissibly allowed reconsideration of the claim and did not offend separation of powers.
- The Court held the 1877 Act effected a taking of the Sioux’s treaty-protected property.
- The Court approved an award of just compensation that included interest from the time of the taking to make the tribe whole.

## Legal Principles

- Congress may waive sovereign immunity and remove preclusion barriers to permit adjudication of claims against the United States, so long as it does not dictate outcomes in particular cases.
- Treaty-based tribal interests in reserved lands can constitute “property” protected by the Fifth Amendment’s Just Compensation Clause.
- Governmental destruction of treaty-protected land rights may be treated as an exercise of eminent domain requiring compensation, even in the context of federal authority over Indian affairs.
- “Just compensation” requires placing the owner in the same pecuniary position as if the property had not been taken; this may require interest from the date of taking.
- Findings of coercion, lack of meaningful consent, and government failure to protect treaty rights support characterizing a statutory transfer of tribal land as a taking rather than a voluntary cession.

## Conclusion

The Court upheld Congress’s authority to reopen the Sioux Nation’s Black Hills claim for judicial determination and held that the 1877 seizure of treaty-reserved land was a Fifth Amendment taking, requiring payment of the land’s value with interest from 1877.


United States v. Sioux Nation of Indians, 448 U.S. 371 (1980)